The present invention is related to the field of data storage.
Data storage systems may employ a block file system to manage the use of physical storage resources (e.g., areas of physical disks) in providing higher-level logical units of storage to applications or users in a data processing system. This is particularly the case for storage systems supporting mapped logical units (MLUs) used in “thin provisioning” schemes of storage allocation, where physical storage resources are assigned to logical units of storage dynamically as needed during operation rather than statically at an initial time of configuration. The block file system defines a corresponding file for each MLU and conducts block-level file-access operations in satisfaction of storage input/output requests (reads and writes) directed to the MLU. Here “block-level” refers to operations on fixed-size data units called “blocks”, a technique long known in the computing industry. One example of a block file system is the Common Block File System (CBFS) utilized in storage products manufactured and sold by EMC Corporation.